Questions tagged [nfc]

Near Field Communications - In antennae theory Far Field radiation is that RF energy that gets transmitted, Near Field is the RF energy that typically does not propagate , unless it is intercepted by a special antenna. It is used to transmit signals over short distances without transmitting widely, it is used in wireless communications for very short ranges on the order of meters and is harder to intercept because you have to be close.

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44 views

Would a magnet interfere with NFC devices in this scenario?

I am thinking about manufacturing an interactive chessboard as a personal project. The circular pieces (resembling more or less poker chips in shape) would contain NFC tags, so it is possible for the ...
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Typically what range can an active powered type 5 NFC tag be written / read on iOS/Android

does anyone know the answer to the above - I am struggling to find out the information. I know that a type 5 tag can be read from 1.5 metres away in ideal conditions, but what can I expect from a ...
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How to get PN532 reader connected by SPI or UART getting detected by pcsc_scan?

I have a PN532 board with SPI and UART connections both. I would like to get it integrated with PCSC so that it can be detected with pcsc_scan command. As PN532 is compatible with CCID as well. What ...
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33 views

Would a ground plane/traces impact NFC antenna performance?

I am building a PCB business card with an NFC chip and a WS2812B LED display (powered by a USB-C port, NFC is not connected to the LEDs). Right now I have a ground plane on the side of the antenna (...
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47 views

Read data from 125kHz tag and write into 433MHz remote

At the moment, I am opening the garage door via the 125khz key tag. I purchased a 433mhz remote. Also, I have a tool to read/write data from tags and I have used it in the past to copy key tags. I ...
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Low latency passive RFID solution?

I'm an embedded software developer working on a personal project using RFID. I'm attempting to read a passive 13.56 MHz tag moving at 100ft/sec. Given the limited range of passive tags, I'm looking ...
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NFC Antenna Design/Matching without VNA

I would like to design a circuit around the W7002 antenna (Dataheet) and the NXP PN532 NFC Reader Chip. Since I never worked with antenna design before I do not have a VNA and I also don't have ...
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How to measure resistance/voltage with NHS3152 General Starter Kit?

I have just started running NHS3152 General Starter Kit, with the LPC-Link 2 debugger and LPCXpresso as IDE. I have managed to run "App_demo_dp_bLinky" example. However I cannot find an ...
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How to solder wires onto pins of an RFID chip?

I want to integrate a sensor with NXP's NHS3152 (datasheet). To do this I have to solder the wires onto the pins of the RFID chip. What tools should I buy to do this? What is a good reference to learn ...
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NFC tag capacity and read/write speed

I'm designing a project that I need to save data logs into Tags. I've chosen NFC because it has high capacity tags compared with RFID. I've checked the Mifare 8KB cards like this one. I have two ...
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137 views

NFC - design of inductor/“antenna” made of PCB traces

I did a layout of a NFC PCB inductor/"antenna"(I know it is not one exactly) drawn only on top side copper (nothing drawn on other layers at inductor area), and I wonder if there will be a ...
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NFC 13.56MHz RF - Use inductor in place of pcb trace made antenna

I need to make a NFC antenna on NFC tranceiver->LC filter->matching circuit->antenna. Inductance shows to be 1.5uH on an online calculator of nfc antennas. Can I simply just place a good inductor of ...
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32 views

Limiting NFC distance between reader and tag

I plan to do a PCB with an MCU and it will include one NCF reader IC + PCB antenna in the same board. I have pre-selected one of the following ICs: Texas TRF7970A: https://media.digikey.com/pdf/Data%...
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RC522 has other pins than shown in all the tutorials

I've bought an RFID RC522 module which I intend to use with my Raspberry Pi 3B+. I read the following tutorials and I noticed that their modules have other pins than the one I bought: https://www....
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Override value of RFID tag from external sensor

I have the following scenario, there is a RFID tag attached to a certain object which also have a light sensor on it (this is just for illustrative purposes, it could be another type of sensor), I ...
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43 views

NFC Loop Antenna placement

I'm trying to design a NFC loop antenna according to the following specification: http://www.ti.com/lit/an/sloa135a/sloa135a.pdf In the design the loops are placed on the top layer of the PCB, same ...
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NFC tag affected by circuit board?

total noob here. I have a general question regarding the NFC tags: I have a 12mmx19mm NFC tag. I notice I was able detect it (1-1.5cm away) without a problem until I place a circuit board behind it (...
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What material can I use to insulate NFC tags so they can be placed almost back to back?

I have posters with "Tap me to check in/out of this meeting room" drawn on them. I have NFC Stickers behind each poster to send the user to a specific URL in the application. They are being placed on ...
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Find PCB Antenna impedance and matching circuit

I'm working on a project that uses NFC interface. I need to design two antennas: one for the RFID tag and another for the NFC initiator. I decided to use the design proposed in the evaluation kits. ...
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RFID (13.56MHz) GND plane over antenna

I dissasembled multiple RFID devices to study their design. The following reader attracted my attention: This is a four layer PCB, the anntenna seems to be 4-turn symetric and is layed out on the two ...
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318 views

NFC standards ISO 14443, ISO 15693 and ISO 18000-3. Which of them are most supported by smartphones?

I want to do this: mobile app <-> NFC <-> microcontroller, in order the MCU can communicate with Android or iOS apps via NFC hardware. I have two options of low-cost NFC chips, these chips don'...
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46 views

Implement a data protocol between a smartphone and a MCU via NFC hardware?

If I'm able to develop a mobile app which is able to use the NFC hardware of a smartphone to write/read through it. And if I have a board containing a MCU and a NFC transponder like the IC from ST ...
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52 views

Can a NFC tag be read over a large flat area

Was wondering if I could create a large flat area that could detect the position of NFC tag (or similar preferably powerless technology) and if possible the direction the chip is facing. Say if you ...
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RFID/NFC transponder with current delivered via wire

I'm sure everybody here knows how RFID transponder works, reflecting radio waves and receiving them at the source. I'm looking for the same concept, but instead of the input to the transponder being ...
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How can I remove the return paths for a series of circuits and still know when they are completed? NFC/RFID? Multiplexing? Goubau line?

Apologies for the vague title. And know that my electronics knowledge is rather limited. Also my circuit diagrams may be incorrect. I currently have something like this, which represents contacts on ...
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123 views

Why I could not change this eagle NFC class6 antenna footprint?

I am designing a NFC board prototype that uses NT3H1101 chip. For this, I use NXP AN11276 antenna design guide. This document contains sample file download links for class 6 antennas. I downloaded ...
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Large NFC/RFID reader antenna around a screen

I would like to have an NFC/RFID reader with a screen around 7", where one could tap the card anywhere on the screen to have it detected/read. I do not need to know where the card was placed (...
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151 views

PN532 (SPI) how to get firmware version

I am trying to use PN532 for Mifare card reading on STM32F4. Before even trying to go forward I have tried to read firmware version to verify that all works ok and cannot do it. I am trying to base ...
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Screen with built-in NFC

So I've started working on a small project (small at the moment) and I'm seeing some issues in my prototype plans, and I need your help with this. Short answer: I need a led touchscreen with NFC ...
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My cellphone is acting as an RFID tag? [closed]

I bought a cheap keyboard emulating RFID (miFare) reader for my PC. I just noticed that the reader can 'read' my cell phone (Pixel 1 XL). Every read seems to return a different serial number. I can ...
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Passive RFID design assistance

I am looking for the correct RFID tag/reader system for my design. The general block diagram of the system is above. The requirements for the system are as follows: Passive tags of some form and an ...
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95 views

Tracking the location of NFC chips on a board

For a oroject, I am looking to track the location of several game pieces on a game board using NFC chips. This board is made up of a grid and would need to send the location back to a device. I was ...
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31 views

Scalable NFC antenna surface for multiple object detection

as I am absolutely new to NFC and electrical engineering in general (my background is software engineering), I will probably upset users on this Stack with my lack of previous research. But the idea I ...
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54 views

Read T5577 tags with PN532 reader

I am working with adafruit RFID/NFC reader. This reader works with a PN532 chip. This chip is designed to read mifare tags (13.56MHz). I want to read T5577 tags. This tags works at 125 kHz. I am ...
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337 views

Advice on battery powered ESP32 with NFC Design

I'm new to PCB design (First one) and I want some advice and tips from more knowledgeable people in regard to basic design elements and especially the power consumption part. I want to make the ...
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241 views

NFC antenna connection to ground midway through loop

I'm designing a PCB etched NFC antenna. I'm confused about a design element I've seen in several production boards. I haven't seen this element explicitly discussed in any app notes or design guides. ...
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Is there a difference between an NFC and RFID chip?

The other day, my friend said that he wants to write an app that uses the NFC chip on a phone to read pet microchips. I told him I was pretty sure that pet microchips don't use NFC, but he said he was ...
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162 views

NTAG213 Not being picked up by the RC522 Module

I have been using the RC522 module to read and write things to the tags it came with. But when I tried to use an NTAG213 I bought for a recent project it will act as if it isn't there. I've tried a ...
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994 views

External Antenna connection on MFRC522

New to RFID world. I am working on a Healthcare product. One of the feature includes authentication of patients which will be done through RFID reader MFRC522. Application schematic in the datasheet ...
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114 views

can aluminum foils increase the boost the range of nfc reader?

I have been working on a project where I have to read data from an NFC tag and store the information locally. Currently I have a range for the NFC tag of about 5 cm. The tags will be present inside a ...
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IC on Digikey is 5x more expensive than board containing same IC on Alibaba: How? [closed]

I built a prototype using an NFC board I bought from Alibaba for 1$ (https://www.alibaba.com/showroom/rfid-rc522.html). It claims to use the NXP MFRC522 IC, and if I look on the board the chip has ...
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My antenna tuning component values worked on a fresh board previously. Now they're not working. What could be causing this?

This is one of those hardware questions that's making me bang my head against a wall. About six weeks ago I spent a day tuning the NFC antenna on my board. I ended up using ~71pF of shunt capacitance ...
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NFC Antenna Feed Lines

I've designed a number of boards in the past that use NFC but I don't think the RF performance has ever been exceptional. These boards have an NFC chip (generally the STM M24SR64-YMN6T/2) connected to ...
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71 views

Android NFC library - Command not recognized

To access more than 2kb of data from TI Rf430 transponder IC, a custom command (0xC0) in specific format needs to be sent. On sending the custom command, command not recognized (0x01) is the response ...
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159 views

Reading NFC tag from a slightly longer distance

Presently, my problem is that I have this NFC/RFID Tag, and due to the small antenna on the tag, it needs to make direct contact with the reader (presently tested using both a smartphone w/ NFC ...
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87 views

How can I make my RFID reader restrict itself to the tag in the closest proximity and read only this tag?

I'm looking for a way to detect the user closest to a certain object that has the RFID reader attached to it. Therefore I need my RFID reader to restrict itself to the user closest to it and not read ...
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2answers
106 views

NFC spectrum analysis, weird frequencies showing

I apologize for the picture quality, I did not have an opportunity to export the screenshots. I have a problem properly interpreting this signal. The subcarrier peak is visible but the data seems to ...
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181 views

NFC/RFID device sending URL to NFC-enabled smartphone at 20-30cm

I am very new to this so please bear with me. I have read many questions but I haven't quite found a suitable one for what I would like to do. I would need a NFC/HF RFID device able to send an URL to ...
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What is this weird EMV pin on my credit card?

I recently got a Venmo card, which is my first card with contactless support. I was looking at the EMV pins and noticed a very weird design. In the middle of the ground pin there is this long, thin ...
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Can you find what RFID frequency is used in a tag and then edit it? [closed]

A short background: my brother has membership at a gym that uses small RFID tags ("near field", I suppose, as you need to tap them against the spinning gate in order to open it) and after changing his ...